1, circuit diagram
Definition: The circuit diagram that connects the actual position of automobile electrical appliances on the automobile from the power supply to the switch and then to the ground.
Features: the appearance and installation position of the equipment are consistent with the actual situation, which is convenient for making wire harness. The wiring diagram is dense and criss-crossed, which is not convenient to read, find and analyze faults.
2. Schematic diagram
Definition: Each system is arranged according to the circuit principle, and the graphic symbols are concise.
Features:
(1) has a complete concept of vehicle circuit, which is both a complete vehicle circuit diagram and an interrelated local circuit diagram. The key points and difficulties are prominent and the complexity is appropriate.
(2) The concepts of high potential and low potential are established on the diagram: its cathode is grounded (commonly known as ground), and the potential is the lowest, which can be represented by the bottom line in the diagram; The positive electrode "+"has the highest potential, which is indicated by the top line. The direction of current is basically from top to bottom, and the path is: power supply positive pole "ten" → switch → electrical appliance → grounding → power supply negative pole "-".
3. Wiring diagram
Definition: The wiring diagram is a schematic diagram of the whole automobile circuit given by various manufacturers according to the characteristics of their own automobile lines, which is generally given according to the system classification.
Features: The serial number of electrical appliances (that is, electrical equipment) of the whole vehicle is obviously accurate, and the direction of wires is clear, which is easy to follow and find. Distribute wires to each harness according to the harness system, and strictly check the position of each plug-in.
In the vicinity of each switch, the connection and gear control relationship of the switch, the connection relationship between the fuse and the wire, the color and cross-sectional area of the wire are expressed by tabular method.
4. Wiring diagram
Definition: The wiring diagram of vehicle circuit is often used for the connection, maintenance and wiring of assembly lines and repair shops in automobile factories.
Features: the wiring diagram mainly shows the connection parts of electrical appliances, the marks of terminals, the shapes and positions of terminals and connectors, etc. It is an automobile circuit diagram that people can actually touch in the car. Generally speaking, this drawing does not describe the direction of wires inside the harness in detail, but only numbers or marks the wires and connectors exposed outside the harness in detail. This is a prominent assembly mark.